Recent progress of a semiconductor manufacturing technology is extremely remarkable, and semiconductor devices with a minimum feature size of 40 nm are mass-produced. Such miniaturization of a semiconductor device is realized by rapid progress of a micropatterning technology such as a mask process technology, a photolithography technology, and an etching technology. In the generation in which a pattern size is sufficiently large, a plane shape of an integrated circuit pattern that needs to be formed on a wafer is directly written as a design pattern and a mask pattern faithful to the design pattern is manufactured. Then, the manufactured mask pattern is transferred onto the wafer by projection optics, and a pattern approximately the same as the design pattern is formed on the wafer by etching a base with resist as a processing target film.
However, with the progress of miniaturization of an integrated circuit pattern, it has become difficult to faithfully form a pattern in each process. Consequently, a problem arises in that a final finished dimension does not become as a design pattern. Specially, in the lithography process or the etching process that is the most important process for achieving microfabrication, patterns arranged around a pattern that needs to be formed greatly affect the dimension accuracy of the pattern that needs to be formed.
In order to avoid such influence, technologies such as the OPC (Optical Proximity Correction) and the PPC (Process Proximity Correction) are developed. In these technologies, an auxiliary pattern is added in advance or a width of a pattern is thickened or thinned so that a shape of a processed integrated circuit pattern becomes a design pattern (desired value). With the use of the OPC or the PPC, a pattern (design pattern data) written by a designer can be formed on a wafer into approximately a desired shape. In the case of a conventional method using the OPC or the PPC, (1) process of correcting mask pattern data so that a resist dimension and a resist shape transferred onto a wafer have a desired value or (2) process of correcting mask pattern data so that a finished dimension and a finished shape of a final semiconductor circuit pattern transferred onto a wafer have a desired value is performed.
In the case of a mask for forming a minute integrated circuit pattern, a proximity effect occurs also in a process of manufacturing the mask itself. Therefore, there is a problem in that a data value of the mask and an actual finished shape of the mask differ. The OPC and the PPC are methods of correcting mask data based on a relationship between the mask data and a pattern shape on a wafer, so that the actual finished shape of the mask manufactured from the mask data before forming the pattern shape is uncertain.
Therefore, in order to ensure a finished shape of a mask itself, conventionally, one ambient environment (for example, a line & space pattern in which a dimension ratio of a line pattern and a space pattern is 1:1) is selected from a mask pattern and a finished dimension assurance of the mask in the selected ambient environment is performed.
However, with this method, the finished dimension assurance of the mask is performed only in one ambient environment, so that there is a problem in that the finished dimension assurance of the mask is not accurate. Thus, it is desired to accurately perform the finished dimension assurance of a mask pattern.